Cutaneous leishmaniasis. Third World doctor treating a cutaneous leishmaniasis ulcer on the face of a boy. He is using a cream containing the drug paramomycin. Leishmaniasis is a tropical disease caused by Leishmania sp., a parasitic protozoan, which is transmitted by bites from infected sand-flies. This is the less serious form of the disease, where a persistent ulcer develops around the sand-fly bite. While the ulcer eventually heals, scarring is common. Photographed in Iran.